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ICRS Recommendation Document: Patient-Reported Outcome Instruments for Use in Patients with Articular Cartilage Defects.

Roos EM, Engelhart L, Ranstam J, Anderson AF, Irrgang JJ, Marx RG, Tegner Y, Davis AM - Cartilage (2011)

Bottom Line: A major difference between them is that the former results in a single score and the latter results in 5 subscores.Because there is no obvious superiority of either instrument at this time, both outcome measures are recommended for use in cartilage repair.However, activity measures require age and sex adjustment, and data are lacking in people with cartilage repair.

View Article: PubMed Central - PubMed

Affiliation: Unit for Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.

ABSTRACT

Objective: The purpose of this article is to describe and recommend patient-reported outcome instruments for use in patients with articular cartilage lesions undergoing cartilage repair interventions.

Methods: Nonsystematic literature search identifying measures addressing pain and function evaluated for validity and psychometric properties in patients with articular cartilage lesions.

Results: The knee-specific instruments, titled the International Knee Documentation Committee Subjective Knee Form and the Knee injury and Osteoarthritis and Outcome Score, both fulfill the basic requirements for reliability, validity, and responsiveness in cartilage repair patients. A major difference between them is that the former results in a single score and the latter results in 5 subscores. A single score is preferred for simplicity's sake, whereas subscores allow for evaluation of separate constructs at all levels according to the International Classification of Functioning.

Conclusions: Because there is no obvious superiority of either instrument at this time, both outcome measures are recommended for use in cartilage repair. Rescaling of the Lysholm Scoring Scale has been suggested, and confirmatory longitudinal studies are needed prior to recommending this scale for use in cartilage repair. Inclusion of a generic measure is feasible in cartilage repair studies and allows analysis of health-related quality of life and health economic outcomes. The Marx or Tegner Activity Rating Scales are feasible and have been evaluated in patients with knee injuries. However, activity measures require age and sex adjustment, and data are lacking in people with cartilage repair.

No MeSH data available.


Related in: MedlinePlus

The relation between effect size (difference in mean scores relative to the common standard deviation) and sample size for a comparison of 2 groups of patients using a 2-tailed Student t test with 5% significance level and 80% power.
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fig1-1947603510391084: The relation between effect size (difference in mean scores relative to the common standard deviation) and sample size for a comparison of 2 groups of patients using a 2-tailed Student t test with 5% significance level and 80% power.

Mentions: Measures used to evaluate outcomes in patients with cartilage repair need to be responsive; that is, they need to be able to detect change in status when true change has occurred. This change may be within a single group over time, between 2 groups where each experienced a different intervention, or a hybrid where the change over time between 2 groups is considered. Irrespective of the type of change, responsiveness can be reported using an effect size (standardized change score) for paired or unpaired data as appropriate.17 Effect size is usually calculated as the difference between the mean before treatment and after treatment and dividing it by the standard deviation of the same measure before treatment.18 Dividing the mean score change by the standard deviation of that score change is usually referred to as the standardized response mean (SRM).19 For example, in the study by Bekkers et al.,20 effect sizes ranging from 0.70 to 1.32 were seen in the KOOS subscales 3 years after autologous cartilage implantation or microfracture (Table 2). In this case, the effect size can be used for calculation of sample size in future studies of these interventions. An effect size of 0.70 implies that 18 patients would be needed to be able to detect a statistical difference within a single group of subjects from before to after treatment with a power of 80% and an alpha level of .05. An effect size of 1.32 implies that only 7 patients would be needed to detect a change over time within a single group of subjects (Figure 1). In the study by Greco et al.,3 the responsiveness of 4 different PROs was determined for a case mix of patients with traumatic cartilage lesions, osteochondritis dissecans, OA, or other diagnoses. The patients had 1 of 6 articular cartilage procedures and, in 40 cases, 1 or more of 12 associated procedures. In this study, the effect sizes reported from the application of the 4 different instruments applied can be compared to each other to determine the most responsive instrument. However, the effect sizes cannot reliably be used for calculation of sample size in future clinical trials of cartilage repair as responsiveness of a measure is based on the context of the participants who comprise the sample and the intervention. An effect size based on patient-reported perceived longitudinal change, as in the examples above, cannot be used to calculate sample size for a between-group analysis. Often the difference in patient-reported outcome between groups is smaller than the longitudinal change within each group, necessitating a larger sample size to detect a significant difference between groups. Sample size is further discussed under “Statistical Issues.”


ICRS Recommendation Document: Patient-Reported Outcome Instruments for Use in Patients with Articular Cartilage Defects.

Roos EM, Engelhart L, Ranstam J, Anderson AF, Irrgang JJ, Marx RG, Tegner Y, Davis AM - Cartilage (2011)

The relation between effect size (difference in mean scores relative to the common standard deviation) and sample size for a comparison of 2 groups of patients using a 2-tailed Student t test with 5% significance level and 80% power.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4300781&req=5

fig1-1947603510391084: The relation between effect size (difference in mean scores relative to the common standard deviation) and sample size for a comparison of 2 groups of patients using a 2-tailed Student t test with 5% significance level and 80% power.
Mentions: Measures used to evaluate outcomes in patients with cartilage repair need to be responsive; that is, they need to be able to detect change in status when true change has occurred. This change may be within a single group over time, between 2 groups where each experienced a different intervention, or a hybrid where the change over time between 2 groups is considered. Irrespective of the type of change, responsiveness can be reported using an effect size (standardized change score) for paired or unpaired data as appropriate.17 Effect size is usually calculated as the difference between the mean before treatment and after treatment and dividing it by the standard deviation of the same measure before treatment.18 Dividing the mean score change by the standard deviation of that score change is usually referred to as the standardized response mean (SRM).19 For example, in the study by Bekkers et al.,20 effect sizes ranging from 0.70 to 1.32 were seen in the KOOS subscales 3 years after autologous cartilage implantation or microfracture (Table 2). In this case, the effect size can be used for calculation of sample size in future studies of these interventions. An effect size of 0.70 implies that 18 patients would be needed to be able to detect a statistical difference within a single group of subjects from before to after treatment with a power of 80% and an alpha level of .05. An effect size of 1.32 implies that only 7 patients would be needed to detect a change over time within a single group of subjects (Figure 1). In the study by Greco et al.,3 the responsiveness of 4 different PROs was determined for a case mix of patients with traumatic cartilage lesions, osteochondritis dissecans, OA, or other diagnoses. The patients had 1 of 6 articular cartilage procedures and, in 40 cases, 1 or more of 12 associated procedures. In this study, the effect sizes reported from the application of the 4 different instruments applied can be compared to each other to determine the most responsive instrument. However, the effect sizes cannot reliably be used for calculation of sample size in future clinical trials of cartilage repair as responsiveness of a measure is based on the context of the participants who comprise the sample and the intervention. An effect size based on patient-reported perceived longitudinal change, as in the examples above, cannot be used to calculate sample size for a between-group analysis. Often the difference in patient-reported outcome between groups is smaller than the longitudinal change within each group, necessitating a larger sample size to detect a significant difference between groups. Sample size is further discussed under “Statistical Issues.”

Bottom Line: A major difference between them is that the former results in a single score and the latter results in 5 subscores.Because there is no obvious superiority of either instrument at this time, both outcome measures are recommended for use in cartilage repair.However, activity measures require age and sex adjustment, and data are lacking in people with cartilage repair.

View Article: PubMed Central - PubMed

Affiliation: Unit for Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.

ABSTRACT

Objective: The purpose of this article is to describe and recommend patient-reported outcome instruments for use in patients with articular cartilage lesions undergoing cartilage repair interventions.

Methods: Nonsystematic literature search identifying measures addressing pain and function evaluated for validity and psychometric properties in patients with articular cartilage lesions.

Results: The knee-specific instruments, titled the International Knee Documentation Committee Subjective Knee Form and the Knee injury and Osteoarthritis and Outcome Score, both fulfill the basic requirements for reliability, validity, and responsiveness in cartilage repair patients. A major difference between them is that the former results in a single score and the latter results in 5 subscores. A single score is preferred for simplicity's sake, whereas subscores allow for evaluation of separate constructs at all levels according to the International Classification of Functioning.

Conclusions: Because there is no obvious superiority of either instrument at this time, both outcome measures are recommended for use in cartilage repair. Rescaling of the Lysholm Scoring Scale has been suggested, and confirmatory longitudinal studies are needed prior to recommending this scale for use in cartilage repair. Inclusion of a generic measure is feasible in cartilage repair studies and allows analysis of health-related quality of life and health economic outcomes. The Marx or Tegner Activity Rating Scales are feasible and have been evaluated in patients with knee injuries. However, activity measures require age and sex adjustment, and data are lacking in people with cartilage repair.

No MeSH data available.


Related in: MedlinePlus